CN105427380A - Three-dimensional map data processing method based on multiple detailed layers - Google Patents
Three-dimensional map data processing method based on multiple detailed layers Download PDFInfo
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Abstract
A three-dimensional map data processing method based on multiple detailed layers comprises three steps including digital orthographic image cutting, digital altitude data cutting, altitude data inlaying and edging. The highest three-dimensional map precision reaches 20 m at present. When a sight point is close with a surface texture, a single texture pixel will cover multiple pixel points under effects of a texture amplifier, so that an image becomes very vague. The three-dimensional map data processing method based on the multiple detailed layers provided by the invention increases definition of a three-dimensional map during display, wherein landform details are closer to real landform conditions; and real-time access performance of the three-dimensional map is enhanced by a database storage technology based on a three-dimensional model, pressure to a database server during access to the three-dimensional map is reduced, and concurrent access performance is also increased simultaneously.
Description
Technical field
The invention belongs to electrical network three-dimensional map data disposal route.
Background technology
Along with the development of GIS technology, three-dimension GIS obtains applying more and more widely in whole power industry, based on the three-dimensional simulation of real scene data, demonstrates outstanding effect in various aspects such as administration of power networks, breakdown repair, security monitorings.By means of superior image, data qualification, the technology such as advanced GIS, RS and virtual reality are utilized digital terrain model, power transmission and transforming equipment model and various power department professional attributes information to be combined, set up electric power three-dimensional geographic information platform, the inquiry of the power specialty data combined with Fundamental Geographic Information Data, renewal can be realized, the maintenance of mains-power circuit and safe prosecution, the space realizing electrical network in large scene shows and analyzes, management function.Platform is by advanced three-dimensional visualization means, include whole power transmission and transformation business and management overall process in computer management, specification power transmission and transformation operation flow, strengthens cooperation and the management function of power department, improves geographical department operation of transmission lines and substations, managerial ability and level of decision-making.
Existing three-dimensional map precision is up to 20 meters at present, and time view distance superficial makings is nearer, single texture pixel, under the effect of texture amplifier, can cover multiple pixel, and this just makes image become very fuzzy.
On the other hand, high resolution image comprises more surface details really, but these details are all often closely similar.There is provided such details will consume a large amount of texture memories undoubtedly, although this gives a clue to decision height and action, avoid the fuzzy of surface, cause texture memory inadequate, so that a lot of really useful information cannot load in time, successfully.
Summary of the invention
The present invention is just in order to overcome one that above-mentioned defect designs based on detail three-dimensional map data disposal route, and the present invention is achieved by the following technical solution:
A kind of based on detail three-dimensional map data disposal route, the present invention is characterised in that, comprises 3 steps: digital orthoimage cutting, the cutting of digital elevation data, altitude figures are inlayed and edge fit; Wherein:
Digital orthoimage cuts: digital orthoimage cutting is tile satellite image picture being cut into 256*256 pixel according to pyramid model, the tile cut carries out coding name according to the form of l_r_c.png, l is the level number of pyramid model, r is the line number of pyramid model, and c is the row number of pyramid model;
Digital elevation data are cut: the cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to pyramid model on irregular basis sets up dem data; The small cubes cut sets up index according to level, row, column, block, and is stored into database with the form of OBJ;
Altitude figures edge fit and inlaying: based on the small cubes of digital elevation data cutting, choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, then be considered as transfiniting, regarded as rough error point, and re-established body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method; If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got, as the height value of respective grid points to the elevation of all same level coordinate net lattice points participating in edge fit.
A kind of based on detail three-dimensional map data disposal route, the present invention is characterised in that, adopts following technological means:
1) tile pyramid structure is set up
Tile map pyramid model is a kind of multiresolution hierarchical model, and from the pyramidal bottom of tile to top layer, resolution is more and more lower, but the geographic range represented is constant, mainly comprises tile and pyramid two parts; Wherein:
1.1) tile
Described tile is exactly, according to certain proportional sizes, piece image is divided into some little square grids, and each grid is exactly a tile;
Map tile after section is grating image, does not have locating information, but after section used related slices algorithm, can calculate the position of concrete location.
1.2) pyramid model
According to the demand of user, piece image is divided into ascending region.After segmentation, image forms that ratio is ascending, and quantity pyramid structure from less to more: Fig. 1 is pyramid planar structure, and Fig. 2 is pyramid structure intuitively.
Tile is little square block, and length and width are equal, and length and width length is 256 pixels, 8 ~ 18 grades of totally 11 grades of engineer's scales; Engineer's scale rank increases one-level; Coding name is carried out according to the form of " l_r_c.png " after having cut; Wherein l is engineer's scale rank, and r is line number, and c is row number, 0<=r<=2
aa, 0<=c<=2
aa; According to above-mentioned picture cutting coding rule, obtain the mutual conversion between picture ranks coordinate and actual geographic coordinate, these are bases of map denotation.
longitude and latitude is converted to line number under certain engineer's scale and row number, and transfer process is:
n＝Math.pow(2,lev)
x＝((Longitude+180)/360)*n
sinLat＝Math.Sin(Math.PI*Latitude/180)；
y＝0.5-Math.Log((1+sinLat)/(1-sinLat))/(4*Math.PI)；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Sin is sine function, and Math.Log is for taking the logarithm.
line number under certain engineer's scale and row number are converted to longitude and latitude, and transfer process is:
n＝Math.pow(2,lev)
Longitude＝x/n*360-180；
Latitude＝Math.Atan(Math.Sinh(Math.PI*(1-2*y/n)))；
Latitude＝Latitude*180.0/Math.PI；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Atan is arctan function, and Math.Sinh is hyperbolic sine function.
2) DEM terrain data cutting
Digital elevation model, vehicle economy M; It is a kind of actual ground model representing ground elevation by one group of orderly array of values form, and be a branch of digital terrain model, other various topographic index all can derive from thus; It is generally acknowledged, DTM describes the various geomorphologic factors comprising elevation, as the space distribution that the factors such as the gradient, slope aspect, change of slope combine at interior linear processes, wherein DEM is the individual event digital land value model model that zeroth order is simple, and other can derive from as landforms characteristics such as the gradient, slope aspect and change of slopes on the basis of DEM.
TIN, is called for short TIN; Directly utilize original sample point to carry out the reconstruction of topographical surface, the triangular facet be coupled to each other by continuous print forms, and the shape of triangular facet and size depend on density and the position of the observation station of irregular distribution.
The cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to the layer of pyramid model, row, column on irregular basis sets up dem data; With the resolution of different levels, surface configuration can be described; More complicated surface can be represented more accurately with less room and time under a certain specified resolution; Special in landform includes large measure feature as fracture line, tectonic line, these features can be taken better into account; The small cubes cut sets up joint index according to level, row, column, block, and is stored into database with the form of OBJ.
Platform is directly resolved obj file, and the information such as model vertices, pinup picture that obtains is stored in database by specification format preserves, and the key element of parsing as shown in Figure 3.
3) altitude figures edge fit and inlaying
3.1) DEM is edited
Dem data editor refers to that the DEM grid points to interpolation is formed is edited one by one; Identical terrain category DEM grid points edge fit limit difference is the twice of this terrain category grid points medial error, and different terrain classification DEM edge fit limit difference is two kinds of terrain category DEM grid points edge fit limit difference sums.
3.2) dem data edge fit
Choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, be then considered as transfiniting, regarded as rough error point, and re-establish body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method.
3.3) dem data is inlayed and is cut
If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got to the elevation of all same level coordinate net lattice points participating in edge fit, as the height value of respective grid points, form the match accuracy report on each bar limit simultaneously.
After DEM has inlayed, the start-stop grid points coordinate specified according to relevant regulations or technical requirement carries out rectangle when cutting, and can extend out a row or multi-row DEM graticule mesh according to specific requirement.
4) DEM quality control
The quality control of DEM comprises production run quality control and end result quality control two parts.
4.1) production run quality control
Whether correctness and the data of the key points of quality control inspection source book use in production run are reasonable.
Whether the layering in lake, reservoir, two-wire river is reasonable, and whether the elevation assignment in waterside line and shore line is rationally correct, and within the scope of static water body, DEM height value should be consistent, and the DEM height value in flowing waters should gentle transition from top to bottom, and relation is reasonable.
The region not reaching the requirement of regulation vertical accuracy should divide DEM elevation into and infer district.
The graticule mesh being positioned at white space should give height value-9999, will intactly record in the metadata to the process of clear area.
4.2) end result quality control
The method of DEM interpolated contour is passed through in the quality control of end result, and whether visual examination level line has catastrophe, or compares with topomap, when landform shape, same place elevation differ greatly, then judges there are quality problems and modify.
Check the correctness of dem data terminal coordinate, check that whether height value effective range is correct.
Should check after DEM splicing, determine whether overlap and crack, whether splicing precision reaches requirement.
Normally used DEM file is gray-scale map, and its processing procedure as shown in Figure 4.
The coordinate information of model is stored in the fixing Double array of a structure, first coordinate information can be read in models show process, in order to judge whether this model shows, during display, go the data of database reading model again, reduce interaction times and the data volume of network with this.Concrete coordinate information storage organization as shown in Figure 5.
Striograph, as the significant data of three-dimensional scenic, is kept in oracle database, and its warehouse-in process as shown in Figure 6.Fig. 7 is model warehouse-in process.
Key point of the present invention is:
1, the three-dimensional map data treatment technology of detail.
2, based on the three-dimensional map data library storage technology of ObjModel.
Compared with prior art, the present invention has advantage or beneficial effect is:
1, improve the sharpness of three-dimensional map when showing, the landforms situation of relief detail more closer to reality;
2, by improve the real time access performance of three-dimensional map based on the database storage techniques of three-dimensional model, database server pressure when reducing access three-dimensional map improves Concurrency Access performance simultaneously.
Accompanying drawing explanation
Fig. 1 is pyramid planar structure;
Fig. 2 is pyramid structure intuitively;
Fig. 3 be platform directly obj file is resolved want sketch map;
Fig. 4 is the processing procedure of DEM file;
Fig. 5 is coordinate information storage node composition;
Fig. 6 is that flat image figure puts process in storage;
Fig. 7 is model warehouse-in process.
Embodiment
See Fig. 1-Fig. 7, a kind of based on detail three-dimensional map data disposal route, the present invention is characterised in that, comprises 3 steps: digital orthoimage cutting, the cutting of digital elevation data, altitude figures are inlayed and edge fit; Wherein:
Digital orthoimage cuts: digital orthoimage cutting is tile satellite image picture being cut into 256*256 pixel according to pyramid model, the tile cut carries out coding name according to the form of l_r_c.png, l is the level number of pyramid model, r is the line number of pyramid model, and c is the row number of pyramid model;
Digital elevation data are cut: the cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to pyramid model on irregular basis sets up dem data; The small cubes cut sets up index according to level, row, column, block, and is stored into database with the form of OBJ;
Altitude figures edge fit and inlaying: based on the small cubes of digital elevation data cutting, choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, then be considered as transfiniting, regarded as rough error point, and re-established body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method; If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got, as the height value of respective grid points to the elevation of all same level coordinate net lattice points participating in edge fit.
A kind of based on detail three-dimensional map data disposal route, the present invention is characterised in that, adopts following technological means:
1) tile pyramid structure is set up
Tile map pyramid model is a kind of multiresolution hierarchical model, and from the pyramidal bottom of tile to top layer, resolution is more and more lower, but the geographic range represented is constant, mainly comprises tile and pyramid two parts; Wherein:
1.1) tile
Described tile is exactly, according to certain proportional sizes, piece image is divided into some little square grids, and each grid is exactly a tile;
Map tile after section is grating image, does not have locating information, but after section used related slices algorithm, can calculate the position of concrete location;
1.2) pyramid model
Tile is little square block, and length and width are equal, and length and width length is 256 pixels, 8 ~ 18 grades of totally 11 grades of engineer's scales; Engineer's scale rank increases one-level; Coding name is carried out according to the form of " l_r_c.png " after having cut; Wherein l is engineer's scale rank, and r is line number, and c is row number, 0<=r<=2
aa, 0<=c<=2
aa;
According to above-mentioned picture cutting coding rule, obtain the mutual conversion between picture ranks coordinate and actual geographic coordinate, these are bases of map denotation;
longitude and latitude is converted to line number under certain engineer's scale and row number, and transfer process is:
n＝Math.pow(2,lev)
x＝((Longitude+180)/360)*n
sinLat＝Math.Sin(Math.PI*Latitude/180)；
y＝0.5-Math.Log((1+sinLat)/(1-sinLat))/(4*Math.PI)；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Sin is sine function, and Math.Log is for taking the logarithm;
line number under certain engineer's scale and row number are converted to longitude and latitude, and transfer process is:
n＝Math.pow(2,lev)
Longitude＝x/n*360-180；
Latitude＝Math.Atan(Math.Sinh(Math.PI*(1-2*y/n)))；
Latitude＝Latitude*180.0/Math.PI；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Atan is arctan function, and Math.Sinh is hyperbolic sine function;
2) DEM terrain data cutting
Digital elevation model, vehicle economy M; It is a kind of actual ground model representing ground elevation by one group of orderly array of values form, and be a branch of digital terrain model, other various topographic index all can derive from thus; It is generally acknowledged, DTM describes the various geomorphologic factors comprising elevation, as the space distribution that the factors such as the gradient, slope aspect, change of slope combine at interior linear processes, wherein DEM is the individual event digital land value model model that zeroth order is simple, and other can derive from as landforms characteristics such as the gradient, slope aspect and change of slopes on the basis of DEM;
TIN, is called for short TIN; Directly utilize original sample point to carry out the reconstruction of topographical surface, the triangular facet be coupled to each other by continuous print forms, and the shape of triangular facet and size depend on density and the position of the observation station of irregular distribution;
The cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to the layer of pyramid model, row, column on irregular basis sets up dem data; With the resolution of different levels, surface configuration can be described; More complicated surface can be represented more accurately with less room and time under a certain specified resolution; Special in landform includes large measure feature as fracture line, tectonic line, these features can be taken better into account; The small cubes cut sets up joint index according to level, row, column, block, and is stored into database with the form of OBJ;
3) altitude figures edge fit and inlaying
3.1) DEM is edited
Dem data editor refers to that the DEM grid points to interpolation is formed is edited one by one; Identical terrain category DEM grid points edge fit limit difference is the twice of this terrain category grid points medial error, and different terrain classification DEM edge fit limit difference is two kinds of terrain category DEM grid points edge fit limit difference sums;
3.2) dem data edge fit
Choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, be then considered as transfiniting, regarded as rough error point, and re-establish body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method;
3.3) dem data is inlayed and is cut
If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got to the elevation of all same level coordinate net lattice points participating in edge fit, as the height value of respective grid points, form the match accuracy report on each bar limit simultaneously;
After DEM has inlayed, the start-stop grid points coordinate specified according to relevant regulations or technical requirement carries out rectangle when cutting, and can extend out a row or multi-row DEM graticule mesh according to specific requirement;
4) DEM quality control
The quality control of DEM comprises production run quality control and end result quality control two parts;
4.1) production run quality control
Whether correctness and the data of the key points of quality control inspection source book use in production run are reasonable;
Whether the layering in lake, reservoir, two-wire river is reasonable, and whether the elevation assignment in waterside line and shore line is rationally correct, and within the scope of static water body, DEM height value should be consistent, and the DEM height value in flowing waters should gentle transition from top to bottom, and relation is reasonable;
The region not reaching the requirement of regulation vertical accuracy should divide DEM elevation into and infer district;
The graticule mesh being positioned at white space should give height value-9999, will intactly record in the metadata to the process of clear area;
4.2) end result quality control
The method of DEM interpolated contour is passed through in the quality control of end result, and whether visual examination level line has catastrophe, or compares with topomap, when landform shape, same place elevation differ greatly, then judges there are quality problems and modify;
Check the correctness of dem data terminal coordinate, check that whether height value effective range is correct;
Should check after DEM splicing, determine whether overlap and crack, whether splicing precision reaches requirement.
Claims (2)
1. based on a detail three-dimensional map data disposal route, it is characterized in that, comprise 3 steps: digital orthoimage cutting, the cutting of digital elevation data, altitude figures are inlayed and edge fit; Wherein:
Digital orthoimage cuts: digital orthoimage cutting is tile satellite image picture being cut into 256*256 pixel according to pyramid model, the tile cut carries out coding name according to the form of l_r_c.png, l is the level number of pyramid model, r is the line number of pyramid model, and c is the row number of pyramid model;
Digital elevation data are cut: the cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to pyramid model on irregular basis sets up dem data; The small cubes cut sets up index according to level, row, column, block, and is stored into database with the form of OBJ;
Altitude figures edge fit and inlaying: based on the small cubes of digital elevation data cutting, choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, then be considered as transfiniting, regarded as rough error point, and re-established body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method; If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got, as the height value of respective grid points to the elevation of all same level coordinate net lattice points participating in edge fit.
2. one according to claim 1 is based on detail three-dimensional map data disposal route, it is characterized in that, adopts following technological means:
1) tile pyramid structure is set up
Tile map pyramid model is a kind of multiresolution hierarchical model, and from the pyramidal bottom of tile to top layer, resolution is more and more lower, but the geographic range represented is constant, mainly comprises tile and pyramid two parts; Wherein:
1.1) tile
Described tile is exactly, according to certain proportional sizes, piece image is divided into some little square grids, and each grid is exactly a tile;
Map tile after section is grating image, does not have locating information, but after section used related slices algorithm, can calculate the position of concrete location;
1.2) pyramid model
Tile is little square block, and length and width are equal, and length and width length is 256 pixels, 8 ~ 18 grades of totally 11 grades of engineer's scales; Engineer's scale rank increases one-level; Coding name is carried out according to the form of " l_r_c.png " after having cut; Wherein l is engineer's scale rank, and r is line number, and c is row number, 0<=r<=2
aa, 0<=c<=2
aa;
According to above-mentioned picture cutting coding rule, obtain the mutual conversion between picture ranks coordinate and actual geographic coordinate, these are bases of map denotation;
longitude and latitude is converted to line number under certain engineer's scale and row number, and transfer process is:
n＝Math.pow(2,lev)
x＝((Longitude+180)/360)*n
sinLat＝Math.Sin(Math.PI*Latitude/180)；
y＝0.5-Math.Log((1+sinLat)/(1-sinLat))/(4*Math.PI)；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Sin is sine function, and Math.Log is for taking the logarithm;
line number under certain engineer's scale and row number are converted to longitude and latitude, and transfer process is:
n＝Math.pow(2,lev)
Longitude＝x/n*360-180；
Latitude＝Math.Atan(Math.Sinh(Math.PI*(1-2*y/n)))；
Latitude＝Latitude*180.0/Math.PI；
Wherein, Longitude is longitude, and Latitude is latitude value, and lev is level of zoom, and Math.pow is the lev power of calculating 2, and Math.PI is circular constant, and Math.Atan is arctan function, and Math.Sinh is hyperbolic sine function;
2) DEM terrain data cutting
Digital elevation model, vehicle economy M; It is a kind of actual ground model representing ground elevation by one group of orderly array of values form, and be a branch of digital terrain model, other various topographic index all can derive from thus; It is generally acknowledged, DTM describes the various geomorphologic factors comprising elevation, as the space distribution that the factors such as the gradient, slope aspect, change of slope combine at interior linear processes, wherein DEM is the individual event digital land value model model that zeroth order is simple, and other can derive from as landforms characteristics such as the gradient, slope aspect and change of slopes on the basis of DEM;
TIN, is called for short TIN; Directly utilize original sample point to carry out the reconstruction of topographical surface, the triangular facet be coupled to each other by continuous print forms, and the shape of triangular facet and size depend on density and the position of the observation station of irregular distribution;
The cutting of digital elevation data is that level line and spot elevation are set up TIN, and the small cubes then cutting into 256*256*256 pixel according to the layer of pyramid model, row, column on irregular basis sets up dem data; With the resolution of different levels, surface configuration can be described; More complicated surface can be represented more accurately with less room and time under a certain specified resolution; Special in landform includes large measure feature as fracture line, tectonic line, these features can be taken better into account; The small cubes cut sets up joint index according to level, row, column, block, and is stored into database with the form of OBJ;
3) altitude figures edge fit and inlaying
3.1) DEM is edited
Dem data editor refers to that the DEM grid points to interpolation is formed is edited one by one; Identical terrain category DEM grid points edge fit limit difference is the twice of this terrain category grid points medial error, and different terrain classification DEM edge fit limit difference is two kinds of terrain category DEM grid points edge fit limit difference sums;
3.2) dem data edge fit
Choose the dem data that consecutive phantom generates, check the elevation of same level coordinate grid site, if there is the poor grid points being greater than 2 times of DEM mean square error of height of elevation, be then considered as transfiniting, regarded as rough error point, and re-establish body Model; To occurring that the dem data of rough error point carries out edge fit and to repair after survey edge fit again; To complete between all single model dem datas in succession successively by above method;
3.3) dem data is inlayed and is cut
If the poor requirement that all conforms with the regulations of the edge fit of all single model dem datas in fixed range, then the tile that digital orthoimage can be used to cut is inlayed DEM; When inlaying, its mean value is got to the elevation of all same level coordinate net lattice points participating in edge fit, as the height value of respective grid points, form the match accuracy report on each bar limit simultaneously;
After DEM has inlayed, the start-stop grid points coordinate specified according to relevant regulations or technical requirement carries out rectangle when cutting, and can extend out a row or multi-row DEM graticule mesh according to specific requirement;
4) DEM quality control
The quality control of DEM comprises production run quality control and end result quality control two parts;
4.1) production run quality control
Whether correctness and the data of the key points of quality control inspection source book use in production run are reasonable;
Whether the layering in lake, reservoir, two-wire river is reasonable, and whether the elevation assignment in waterside line and shore line is rationally correct, and within the scope of static water body, DEM height value should be consistent, and the DEM height value in flowing waters should gentle transition from top to bottom, and relation is reasonable;
The region not reaching the requirement of regulation vertical accuracy should divide DEM elevation into and infer district;
The graticule mesh being positioned at white space should give height value-9999, will intactly record in the metadata to the process of clear area;
4.2) end result quality control
The method of DEM interpolated contour is passed through in the quality control of end result, and whether visual examination level line has catastrophe, or compares with topomap, when landform shape, same place elevation differ greatly, then judges there are quality problems and modify;
Check the correctness of dem data terminal coordinate, check that whether height value effective range is correct;
Should check after DEM splicing, determine whether overlap and crack, whether splicing precision reaches requirement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510979549.4A CN105427380B (en) | 2015-12-23 | 2015-12-23 | One kind is based on detail three-dimensional map data processing method |
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| CN107393008A (en) * | 2017-05-31 | 2017-11-24 | 陈树铭 | Global geographic framework TIN pyramid modeling and method |
| CN109427063A (en) * | 2017-08-30 | 2019-03-05 | 广州极飞科技有限公司 | The storage method and device of image data |
| CN107992588B (en) * | 2017-12-11 | 2020-08-25 | 国网技术学院 | Terrain display system based on elevation tile data |
| CN107992588A (en) * | 2017-12-11 | 2018-05-04 | 国网技术学院 | A kind of gound-mapping system based on elevation tile data |
| CN109933559A (en) * | 2017-12-15 | 2019-06-25 | 国网上海市电力公司 | A kind of data displaying optimization method based on power business |
| CN108052642A (en) * | 2017-12-22 | 2018-05-18 | 重庆邮电大学 | Electronic Chart Display method based on tile technology |
| CN108108575A (en) * | 2018-01-17 | 2018-06-01 | 河南省水利勘测设计研究有限公司 | High-precision engineering dimensional topography production method based on BIM Cross Platform Technologies |
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| CN108830929A (en) * | 2018-05-21 | 2018-11-16 | 东南大学 | Multi-resolution Terrain pyramid model generation method and system based on database |
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| CN112084283A (en) * | 2020-09-11 | 2020-12-15 | 广州南方智能技术有限公司 | Terrain image slicing method based on pyramid structure and hierarchical detail model |
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